In recent years, absorbent cores have been proposed in the art, in which large amounts of granular particles are confined within a large number of small spaces (the first patent document). In an absorbent article of this type, granular particles are placed in a predetermined pattern between two base sheets, and the base sheets are bonded together along areas where the granular particles are absent.
The bonded portions between the base sheets are bonded with such a low strength that the base sheets are separated from each other by a separating force generated from swelling of a large number of granular particles within an area when the granular particles absorb moisture to swell. Then, the volume of granular particles that can be accommodated between two base sheets can be increased.